Jan de Vries was born in Holland & trained as a pharmacist. A naturopath since 1960, he has cared for many thousands of people from all over the world. Herbal preparations are the backbone of Jan de Vries' clinics. Over the years he has sourced the best Please seek medical advice if pregnant. Keep out of reach of children. Store in a cool dry place. Generally: 15 to 20 drops in a little water twice daily. Maintenance: 20 drops in water once daily.